S. Alheta, S. Zayan, T. Mahmoud, and A. Gomaa, “Optimization of Friction Stir Spot Welding Process Parameters for AA6061-T4 Aluminium Alloy Plates”, ASRJETS-Journal, vol. 20, no. 1, pp. 244–253, Jun. 2016, Accessed: Sep. 22, 2025. [Online]. Available: https://www.asrjetsjournal.org/American_Scientific_Journal/article/view/1779